Client replication vehicle movement lag

You did not notice lags because you did not switch on the option:
in Sedan blueprint SpringArm set EnableCameraLag = true. Please switch on EnableCameraLag = true and test again.

Yes, I did. I already set Enabled Camera Lag to true when I tested this. Are you saying you’re still seeing this in the master branch? Did you use Master or Promoted branch? What date?

Did you ever resolve this? Seeing the exact same thing as your video in our project. Thanks!

Hey everybody,

Thank you all for your feedback. I have been able to reproduce this issue and have logged it. You can follow it as it moves through the development staff here: https://issues.unrealengine.com/issue/UE-34580

FWIW, it seems to me that the vehicle is jittering, not the camera (i.e. the stuff in the immediate background seems to move smoothly).

I’m logging out and I’m seeing a lot of corrections in UPrimitiveComponent::ApplyRigidBodyState() – on the order of ~2-8 units every 3-8 frames once I get up to speed. Those seem like awfully big corrections to me. Not sure if something with PhysX, vehicles, or replication of physics state changed recently, but I don’t think we saw this problem in 4.10.

Update: Dotting DeltaPos with CurrentState.LinVel shows that the corrections I’m getting are both “forward” and “backward”. Definitely the cause of the jitter.

Thanks Philip,

The vehicle jittering is what is reported in the issue.

If you would like to add a fix yourself using the source code, you can find out more on how to get it here:

https://github.com/EpicGames/Signup